A conventional shoe stiffener as shown in FIG. 1 comprises a core layer 1 consisting of a main resin material of thermoplastic polyurethane and a filler selected from polycarbonate, polyacrylic, polystyrene or other resin materials having high melting point and hardness, an upper and a lower reinforcing net fabric layer 2, 3 disposed on opposite sides of the core layer 2 for sandwiching the core layer 1 in between the upper and lower reinforcing net fabric layers 2, 3 which are made of cotton, nylon, or T/C (Polyethylene Terephthalate/Cotton) fabric.
Such a shoe stiffener is formed as a thin sheet as extruded through a T-die of an extruder to have a dimension of 0.4 mm˜2.0 mm (thickness)×1˜1.5 m (length)×1 m (width), which is then cut into desired shape or size for making a shoe stiffener such as a toe stiffener or a counter stiffener. Since the stiffener shapes are different from one another, much waste or scrap of the shoe stiffener will be produced, which ranges from 10˜20% based on the raw material of the total stiffener.
The stiffener scrap contains long filaments existing in the reinforcing net fabric layers (2, 3), which are difficult to be separated from the resin materials of polyurethane and the filler. So, the scrap is traditionally disposed for incineration or for underground disposal, to thereby cause big problem of environmental protection and thereby waste material resources.
It is therefore expected to disclose a process for efficiently recycling the stiffener scrap for environmental protection and economic re-use of materials.